A PHP Google Adsense Referrals Script Version 2

NOTE: This is only here for historical purposes. The script has since been updated and the latest version is available from:

PHP Adsense-Referrals Script Version 2.1

My original script was very basic but I’ve now extended it further and I’m releasing version 2.

Version 2 allows place of up to 4 referrals (this is the current maximum allowed by Google - Adsense, Firefox, Picasa and Adwords) - one of each type - and will randomly select which referral to display.

The script is installed & configured as before (click here to read the previous article) and its usage is almost the same, except only:

<php g_referral(); ?>

is required, even when wanting to display more than one referral. Just place the code 1-4 times throughout the page you wish to place it upon.

The code:

<php
// Copyright 2006 Paul (paul at tiglo.co.uk - www.tiglo.co.uk)
// Free to use but please keep the copyright in tact

$adsense_pub_id = "ca-test";
$adsense_referral_channel = "xxxxxxxxxxxxx";
$adsense_referral = array('firefox' => 0,
                          'adsense' => 0,
			  'adwords' => 0,
			  'picasa' => 0);
$using_firefox = preg_match("/firefox/i", $_SERVER['HTTP_USER_AGENT']);

function rand_referral() {
  global $using_firefox;
  if($using_firefox == 1) {
     $referral = rand(2,4);
   } else {
     $referral = rand(1,4);
  }
  return $referral;
}

function g_referral() {
  global $adsense_referral;
  global $using_firefox;
  $referrals = 0;

  while($referrals < 1) {
    if(($adsense_referral['firefox'] == 1 OR $using_firefox == 1)
    AND $adsense_referral['adsense'] == 1
    AND $adsense_referral['adwords'] == 1
    AND $adsense_referral['picasa'] == 1) {
      exit;
    }
    $referral = rand_referral();
    if($referral == 1 AND $adsense_referral['firefox'] == 0) {
      firefox_referral();

      $adsense_referral['firefox'] = 1;
      $referrals = $referrals + 1;
    } elseif($referral == 2 AND $adsense_referral['adsense'] == 0) {
      adsense_referral();
      $adsense_referral['adsense'] = 1;
      $referrals = $referrals + 1;
    } elseif($referral == 3 AND $adsense_referral['adwords'] == 0) {
      adwords_referral();
      $adsense_referral['adwords'] = 1;
      $referrals = $referrals + 1;
    } elseif($referral == 4 AND $adsense_referral['picasa'] == 0) {
      picasa_referral();
      $adsense_referral['picasa'] = 1;
      $referrals = $referrals + 1;
    }
  }
}

function firefox_referral() {
  global $adsense_pub_id;
  global $adsense_referral_channel;
?>
<!-- Begin Firefox referral code -->
<script type="text/javascript"><!--
google_ad_client = "<?php print($adsense_pub_id); ?>";
google_ad_width = 120;
google_ad_height = 60;
google_ad_format = "120x60_as_rimg";
google_cpa_choice = "CAAQrc6TlwIaCAiFrvJfRIvdKPm093M";
google_ad_channel = "<?php print($adsense_referral_channel); ?>";
//--></script>
<script type="text/javascript" 
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
<!-- End Firefox referral code -->
<?php
}

function adsense_referral() {
  global $adsense_pub_id;
  global $adsense_referral_channel;
?>
<!-- Begin Adsense referral code -->
<script type="text/javascript"><!--
google_ad_client = "<?php print($adsense_pub_id); ?>";
google_ad_width = 120;
google_ad_height = 60;
google_ad_format = "120x60_as_rimg";
google_cpa_choice = "CAAQ-dOWhAIaCDhxzMnYataRKIHD93M";
google_ad_channel = "<?php print($adsense_referral_channel); ?>";
//--></script>
<script type="text/javascript" 
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
<!-- End Adsense referral code -->
<?php
}

function adwords_referral() {
  global $adsense_pub_id;
  global $adsense_referral_channel;
?>
<!-- Begin Adwords referral code -->
<script type="text/javascript"><!--
google_ad_client = "<?php print($adsense_pub_id); ?>";
google_ad_width = 120;
google_ad_height = 60;
google_ad_format = "120x60_as_rimg";
google_cpa_choice = "CAAQ-NmkgwIaCE0IWWanjWPsKKTP6n4";
google_ad_channel = "<?php print($adsense_referral_channel); ?>";
//--></script>
<script type="text/javascript" 
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
<!-- End Adwords referral code -->
<?php
}

function picasa_referral() {
  global $adsense_pub_id;
  global $adsense_referral_channel;
?>
<!-- Begin Picasa referral code -->
<script type="text/javascript"><!--
google_ad_client = "<?php print($adsense_pub_id); ?>";
google_ad_width = 120;
google_ad_height = 60;
google_ad_format = "120x60_as_rimg";
google_cpa_choice = "CAAQtNGIlAIaCB5Js1fhN80UKJzErYMB";
google_ad_channel = "<?php print($adsense_referral_channel); ?>";
//--></script>
<script type="text/javascript" 
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
<!-- End Picasa referral code -->
<?php
}
?>

If you are having problems using the code, my email address is at the top of the script and in my website’s footer.

UPDATE: I found some bugs which caused the Firefox referral to be displayed even when someone was using Firefox. However, I’ve fixed them now and these updates can be found here.